Here is the full list of all 30 The Legend of Korra achievements. It takes around 15-20 hours to unlock all of the achievements on Windows.
Completed the highest difficulty of Pro-bending.
Completed the game on Extreme difficulty.
Dodged 100 times.
Went into Avatar State 10 times.
Collected every treasure item.
Got 10 Knockouts in Pro-bending matches.
Spirit-bended 200 dark spirits.
Obtained all combos.
Collected 10 cabbages.
Went into Clash Mode 10 times.
Won a Face-Off in a Pro-bending match.
Performed 100 Finishing Moves.
Countered 100 times.
Purchased 12 talismans.
Completed Chapter 8.
Completed all tutorials.
Completed Chapter 7.
Maxed out all bending types.
Completed Chapter 6.
Completed Chapter 5.
Completed a Naga Running sequence without hitting anything.
Completed Chapter 4.
Completed Chapter 3.
Used your first equipped item.
Jumped 100 times.
Entered the Collection Screen for the first time after finding a treasure.
Equip your first item in Korra's Room.
Bought your first item at the shop.
Completed Chapter 2.
Completed Chapter 1.